Jaw assembly for an endoscopic instrument

ABSTRACT

An endoscopic instrument is provided with a hollow tube, first and second end effectors coupled to the hollow tube and having arms biased away from each other, a cylindrical member slidably disposed over the hollow tube, a push/pull wire extending through the tube, a handle assembly coupled to the push/pull wire and the hollow tube, and a disk segment connected to the push/pull wire and connected to the cylindrical member by a crimp in the cylindrical member. When the handle assembly is actuated, the push/pull wire moves the disk segment and hence the cylindrical member relative to the end effectors and causes the cylindrical member to ride over the arms of the end effectors, thereby forcing the end effectors closed or permitting them to open. Preferably, the disk segment has two curved sides which are coupled to the cylindrical member by crimping, and two substantially parallel sides which provide room for the arms of the end effectors so that the disk segment can move relative to the end effectors. The disk segment also includes a central bore for receiving the push/pull wire.

This is a continuation of U.S. Ser. No. 08/440,327, filed May 12, 1995,now issued as U.S. Pat. No. 5,507,296, which is a continuation-in-partof U.S. Ser. No. 08/189,937 filed Feb. 1, 1994, now issued as U.S. Pat.No. 5,542,432.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to endoscopic surgical instruments. Moreparticularly, this invention relates to super-elastic jaw assemblies formultiple sample endoscopic instruments.

2. State of the Art

Endoscopic biopsy procedures are typically performed with an endoscopeand an endoscopic biopsy forceps device (bioptome). The endoscope is along flexible tube carrying fiber optics and having a narrow lumenthrough which the bioptome is inserted. The bioptome typically includesa long flexible coil having a pair of opposed jaws at the distal end andmanual actuation means at the proximal end. Manipulation of theactuation means opens and closes the jaws. During a biopsy tissuesampling operation, the surgeon guides the endoscope to the biopsy sitewhile viewing the biopsy site through the fiber optics of the endoscope.The bioptome is inserted through the narrow lumen of the endoscope untilthe opposed jaws arrive at the biopsy site. While viewing the biopsysite through the fiber optics of the endoscope, the surgeon positionsthe jaws around a tissue to be sampled and manipulates the actuationmeans so that the jaws close around the tissue. A sample of the tissueis then cut and/or torn away from the biopsy site while it is trappedbetween the jaws of the bioptome. Keeping the jaws closed, the surgeonwithdraws the bioptome from the endoscope and then opens the jaws tocollect the biopsy tissue sample.

A biopsy tissue sampling procedure often requires the taking of severaltissue samples either from the same or from different biopsy sites.Unfortunately, most bioptomes are limited to taking a single tissuesample, after which the device must be withdrawn from the endoscope andthe tissue collected before the device can be used again to take asecond tissue sample. The single-sample limitation of most bioptomes isdue to the limited space between the biopsy forceps jaws. Severalattempts have been made to provide an instrument which will allow thetaking of several tissue samples before the instrument must be withdrawnand the samples collected. Problems in providing such an instrumentinclude the extremely small size required by the narrow lumen of theendoscope and the fact that the instrument must be flexible in order tobe inserted through the lumen of the endoscope. Thus, several knownmultiple sample biopsy instruments are precluded from use with anendoscope because of their size and rigidity. These include the "punchand suction type" instruments disclosed in U.S. Pat. No. 3,989,033 toHalpern et al. and No. 4,522,206 to Whipple et al. Both of these deviceshave a hollow tube with a punch at the distal end and a vacuum sourcecoupled to the proximal end. A tissue sample is cut with the punch andsuctioned away from the biopsy site through the hollow tube. It isgenerally recognized, however, that suctioning tissue samples through along narrow flexible bioptome is virtually impossible.

Copending application U.S. Ser. No. 08/189,937 discloses an endoscopicmultiple sample bioptome which allows for the taking of multiple samplesbefore removal of the bioptome from the endoscope. The multiple samplebioptome includes a hollow outer member and an axially displaceableinner member extending therethrough. The proximal ends of the outer andinner members are coupled to an actuator for axially displacing onerelative to the other. The distal end of the outer member is coupled toone of a cylinder having a sharp distal edge and a jaw assembly, whilethe distal end of the inner member is coupled to the other. The jawassembly includes a pair of opposed, preferably toothed jaw cups each ofwhich is coupled by a resilient arm to a base member. The arms are bentto urge the jaws away from each other. The base member is mounted insidethe cylinder and axial movement of the jaw assembly and cylinderrelative to each other draws the arms into the cylinder (or extends thecylinder over the arms) and brings the jaw cups together in a bitingaction. In this manner, multiple samples from a patient can be taken andstored within the jaw assembly before needing to retrieve the bioptomefrom the patient.

A family of alloys known to exhibit unusual elasticity and flexibilityproperties has recently been identified as having useful practicalapplications. These alloys specifically exhibit what is called the shapememory effect. This effect provides that if such an alloy is plasticallydeformed from its original shape at one temperature, it will completelyrecover its original shape on being raised to a higher temperature. Inrecovering their shapes these alloys can produce a displacement or aforce, or a combination, as a function of the temperature. Due to theunique atomic structure necessary for the memory shape effect to takeplace, these alloys exhibit other properties as well, such assuper-elasticity or pseudo-elasticity.

The type of transformation which occurs in the shape memory alloys isknown as a martensitic transformation and changes the material from ahigh temperature form, called austenite, to a low temperature formcalled martensite. For a given shape memory alloy, the transformationbetween martensite form and austenite form occurs at a predictabletemperature, known as the transformation temperature.

In order for an alloy to exhibit the shape-memory effect, it must firstbe bent into the shape to be "memorized" at room temperature. The alloyis then heated until it assumes a high-temperature configuration calledthe beta or parent phase, where the crystal structure of the metalassumes its austenite form which it will "remember". Next, the alloy israpidly cooled so that the atoms in the alloy rearrange themselves intothe crystal form of martensite. The alloy may then be bent into a newshape which it will maintain as long as the temperature remains belowthe transformation temperature. If the alloy is subsequently reheatedabove its transformation temperature so that the alloy molecularstructure reverts to an austenite form, it will recover its previouslymemorized shape. Shape memory alloys exhibit significantly increasedresiliency relative to their non-superelastic counterparts, because theatoms of the memory metal shift back and forth between martensite andaustenite forms, and do not slip into new dislocated configurations asis the case with normal metals.

Useful temperature independent properties are also exhibited bymemory-shape alloys. In an alloy that has a beta phase capable ofproducing martensite under stress, one can observe an unusual elasticproperty called super-elasticity or pseudo-elasticity. In a typicalalloy with this property, the metal exhibits normal elastic behaviorunder stress (that is, it gets longer in some dimensions) until thecritical stress is reached at which point martensite molecularstructures begin to form. With further stress, the specimen continues toelongate, as if it were being plastically deformed. When the stress isremoved, the martensite structure reverts to the parent phase, oraustenite structure, and the metal contracts to its original dimensions,showing no permanent deformation.

Presently, the applications of shape memory materials in medicalapparatuses are very limited. U.S. Pat. No. 4,925,445 to Sakamoto et al.discloses a guide wire for a catheter, where the guide wire has a rigidbody and a flexible distal end made of a memory-shape metal alloy withthe super-elastic properties described above. The distal end of the wireis curved back such that a blunt forward tip is formed. With asuper-elastic distal end, the guide wire can be guided through the bloodvessel of a patient without the risk of permanently deforming the tip ofthe wire, which could result in the tearing of the blood vessel walls orin the misguiding of the wire. U.S. Pat. No. 5,254,130 to Poncet et al.,similarly uses a memory-shaped alloy as a push rod and steering meansfor steering a distal clevis and attached end effectors. As the push rodis extended outside of the housing where it is held prior to deployment,the push rod assumes a remembered configuration relative to the straighthousing, and hence steers the end effectors to a desired position. Otherthan the steering functions disclosed in the Sakamoto et al. and Poncetet al. patents, however, the super-elasticity of shape memory alloys hasnot been used in medical apparatus of the art.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a jaw assembly fora bioptome where at least portions of the jaw assembly are made out of asuperelastic metal.

It is another object of the invention to provide a jaw assembly for anendoscopic multiple sample bioptome where the jaw arms are superelasticand flexible and repeatedly return to desired positions withoutfracturing or deforming.

It is a further object of the invention to provide a jaw assembly for anendoscopic multiple sample bioptome where the arms of the jaw assemblyundergo insignificant plastic deformation even after repeatedly beingopened and forced closed.

It is also an object of the invention to provide a jaw assembly for anendoscopic multiple sample bioptome which is simple to assemble.

In accord with these objects which will be discussed in detail below, anendoscopic bioptome is provided with a jaw assembly, a tubular member,and an axially displaceable wire extending through the tube member,where the distal end of the wire and tubular member are both coupled tothe jaw assembly, and the jaw assembly includes a pair of opposed endeffectors having resilient arms formed from a superelastic metal.According to a first embodiment of the invention, the proximal ends ofthe resilient arms include angled portions, while the distal endsterminate with end effector jaw cups, which are also preferably formedfrom a superelastic metal. The resilient arms urge the jaw cups awayfrom each other. As the resilient arms are formed from a superelasticalloy, they exhibit very high resiliency and durability even afternumerous uses. Other embodiments of the jaw assembly include arms havingmounting holes and cups having radially arranged teeth and closing cams.Another embodiment of the jaw assembly includes arms having proximalsemi-cylindrical portions with distally extending tabs. Different typesof mounting screws are provided for coupling the proximal ends of thearms of the jaws to the distal end of the tubular member.

According to preferred aspects of the invention, the tubular member is aflexible coil, and the proximal portion of each arm is mounted insidethe distal end of the tubular member by means of a threaded screw andwasher (or retaining sleeve) threaded in the coil. The distal end of thewire is coupled to a cylinder which is preferably provided with a knifesharp distal edge. Different embodiments for coupling the distal end ofthe wire to the cylinder are disclosed. The proximal ends of the coiland wire are coupled to a manual actuation means for axially displacingone of the coil and wire relative to the other. Axial movement of thewire relative to the coil moves the cylinder over the arms of the endeffectors and over the necks of the jaw cups, thereby forcing the jawcups together in a biting action.

According to another embodiment of the invention, a laparoscopic typemultiple sample bioptome is provided with the super-elastic jaw assemblyof the invention. The laparoscopic type bioptome is provided with arelatively rigid hollow tube, and a relatively rigid rod which extendstherethrough. The distal end of the rod is coupled to the jaw assemblydescribed in the first embodiment, and the distal end of the tube isprovided with a knife-sharp edge similar to the cylinder edge describedabove. The proximal end of the rod is coupled to a fixed portion of ahandle and the proximal end of the tube is coupled to a movable leverportion of the handle. Movement of the lever of the handle results inlongitudinal movement of the tube relative to the rod and effects andclosing of the jaws as described above.

Additional objects and advantages of the invention will become apparentto those skilled in the art upon reference to the detailed descriptiontaken in conjunction with the provided figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view in partial section of the proximal endof a first embodiment of the invention;

FIG. 1a is a plan view of one hermaphroditic part of a two part spoolaccording to a preferred embodiment of the invention;

FIG. 1b is a side elevation view of the one part of the two part spool;

FIG. 1c proximal end view of the one part of the two part spool;

FIG. 1d is a distal end view of the one part of the two part spool;

FIG. 1e is a broken schematic section illustrating a leaf spring lockingof two parts of the two part spool;

FIG. 2 is an enlarged transparent side elevation view of the distal endof a first embodiment of the invention with the jaws open;

FIG. 3 is an enlarged exploded side view of the distal end of a firstembodiment of the invention;

FIGS. 4a and 4b are respectively a front view of the threaded screw anda front view of the washer of FIG. 3;

FIG. 4c is a cross sectional view taken along line C--C of the arms ofthe jaw assembly shown in FIG. 3;

FIG. 5 is an enlarged transparent side elevation view of the distal endof a first embodiment of the invention with the jaws closed;

FIG. 6 is an enlarged transparent top elevation view of the distal endof a first embodiment of the invention;

FIGS. 7a through 7e are enlarged transparent side elevational views ofthe distal end of the first embodiment, showing a sequence of biopsysampling operations;

FIGS. 7f through 7h are views similar to FIG. 6 showing the cuttingaction of the knife-sharp distal edge of the cylinder;

FIG. 8a is an enlarged broken side elevation view of a differentembodiment of control wire coupling;

FIG. 8b is a cross sectional view along line B--B in FIG. 10a;

FIG. 9a is a view similar to FIG. 8a but of yet another embodiment ofcontrol wire coupling;

FIG. 9b is a cross sectional view along line B--B of FIG. 9a;

FIG. 10 is a broken side elevation view in partial section of a secondembodiment of the invention;

FIG. 10a is an enlarged transparent side elevation view of the jawassembly to push rod and outer tube coupling of the second embodiment ofthe invention of FIG. 10 with the jaws open;

FIG. 11 is an exploded perspective view of another embodiment formounting jaws on the distal end of a coil;

FIG. 11a is a sectional view taken along the line 11a--11a in FIG. 11;

FIG. 11b is a view similar to FIG. 11 with the jaws coupled to thedistal end of the coil;

FIG. 12 is an enlarged exploded side elevation view of anotherembodiment for mounting jaws on the distal end of a coil;

FIG. 12a is a broken perspective view of a jaw arm according to theembodiment of FIG. 12;

FIG. 12b is broken side elevation view of the embodiment of FIG. 12 in apartially assembled state;

FIG. 12c is a sectional view taken along line 12c--12c in FIG. 12b;

FIG. 13 is an exploded side elevation view of a presently preferredembodiment for mounting jaws on the distal end of a coil;

FIG. 13a is an enlarged distal end view of the screw in FIG. 13;

FIG. 13b is a reduced, partially transparent, side elevation view of theembodiment of FIG. 13 as assembled prior to attachment to the distal endof a coil;

FIG. 14 is an enlarged side elevation view of another embodiment forcoupling a cylindrical sleeve to the distal end of a control wire;

FIG. 14a is a top view of the embodiment of FIG. 13; and

FIG. 14b is an enlarged sectional view taken along lines 13b--13b ofFIG. 13.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGS. 1 through 6, a first embodiment of the multiplesample bioptome with the super-elastic flexible jaw assembly is shownand includes a proximal handle portion 12 and a distal end effectorportion 14. A long flexible coil 16, and an axially displaceable controlwire 18 which extends through the coil 16 couples the handle portion 12to the end effector portion 14. The coil 16 is preferably covered with aPTFE, FEP or polyolefin sheath 15 along substantially all of its lengthand a strain relief sleeve 17 covering a portion of the coil whichextends from the handle 12. The coil 16, by its nature is effectivelyinternally threaded and can receive a screw with mating threads, asdiscussed in further detail below, at its open distal end 16a which ispreferably ground flat 16b. The control wire 18 is preferably flexiblebut longitudinally inelastic and is ideally formed from 304 Steel andprovided with an outer diameter of approximately 0.017-0.018 inch. Theproximal handle portion 12 includes a central shaft 20 and adisplaceable spool 22. The proximal end of the shaft 20 is provided witha thumb ring 24 and a longitudinal bore 26 is provided at the distal endof the shaft 20. A longitudinal slot 28 extends from the proximal end ofbore 26 to a point distal of the thumb ring 24. The displaceable spool22 is provided with a cross member 30 which passes through the slot 28in the central shaft 20. The cross member 30 is provided with a centralthrough hole 32 and a radially engaging set screw 34. According to thefirst embodiment of the invention, a short bore 36 and a radiallyengaging set screw 38 are provided in the shaft 20 distal of the thumbring 24 with the bore 36 communicating with the longitudinal slot 28. Inthe first embodiment of the invention, the proximal end of the coil 16extends into the central through hole 32 in the cross member 30 and isfixed there by the set screw 34. The proximal end of the control wire18, passes through slot 28, is inserted into the short bore 36, and heldthere by the set screw 38. From the foregoing, those skilled in the artwill appreciate that relative movement of the shaft 20 and spool 22results in movement of the control wire 18 relative to the coil 16. Suchaction results in actuation of the end effectors as described in detailbelow.

According to a preferred embodiment of the invention, an hermaphroditictwo part snap-together spool is used. FIGS. 1a through 1e illustrate theprincipal features of each part 222a (222b) of a snap together spool.Two identical hermaphroditic parts 222a (222b) each represent one halfof the spool. Each part 222a (222b) is substantially semi-cylindricalwith a spool shaped outer profile. A coil engaging member 224a (224b)extends radially inward within a semi-cylindrical recess 226a (226b)which extends the entire length of the part 222a (222b). Each part 222a(222b) is provided with a pair of diametrically opposed locking tabs228a (228b), 230a (230b) and a pair of diametrically opposed tabreceiving slots 232a (232b), 234a (234b). In addition, each part 222a(222b) is provided with a pair of diametrically opposed guide pins 236a(236b), 238a (238b) and a pair of diametrically opposed pin receivingholes 240a (240b), 242a (242b). From the foregoing, it will beappreciated that when the two parts 222a, 222b are assembled, the guidepins 236a, 238a on part 222a enter the pin receiving holes 240b, 242b,respectively, on part 222b; and the locking tabs 228a, 230a on part 222aenter the tab receiving slots 232b, 234b, respectively, on part 222b.Similarly, the guide pins 236b, 238b on part 222b enter the pinreceiving holes 240a, 242a, respectively, on part 222a; and the lockingtabs 228b, 230b on part 222b enter the tab receiving slots 232a, 234a,respectively, on part 222a. Prior to the snapping the parts together,the proximal end of the coil 16 (FIG. 1) with a crimp band (not shown)on its end is placed between the coil engaging members 224a, 224b. Whenthe parts 222a, 222b are assembled the respective coil engaging members224a, 224b hold the proximal end of the coil securely.

According to a preferred aspect of the two part spool, the tab receivingslots are provided with leaf springs to inhibit the two parts fromcoming apart. FIG. 1e illustrates the leaf spring schematically withreference to the tab 228a on part 222a as it engages the slot 232b onpart 222b. As seen in FIG. 1e, the slot 232b is partially occluded by adepending arm 233b which acts like a leaf spring when it is engaged bythe tab 228a as it enters the slot 232b. After the tab 228a enters theslot 232b, the arm 233b will prevent the tab 228a from rising out of theslot 232b.

Turning now to FIGS. 2 through 6, the end effector portion 14 includes acylindrical sleeve 40, preferably having a knife-sharp distal edge 42,and a jaw assembly 44. The jaw assembly 44 includes a pair of endeffectors 44a, 44b, a screw 102, and a washer or retaining sleeve 104.Each end effector 44a, 44b includes a jaw cup 46a, 46b preferably havinga knife-sharp rim 48a, 48b (or radially arranged teeth as described indetail below), and a resilient, preferably narrow, arm 50a, 50b whichextends proximally from the jaw cup 46a, 46b. The narrow arm 50a, 50b,at its proximal end 51a, 51b, preferably includes a sharply descendingangled portion 52a, 52b, and a gently angled portion 53a, 53b. At leastthe gently angled portion 53a, 53b of the arms 50a, 50b, and preferablythe entire arms 50a, 50b are formed from super-elastic memory metal suchas Nitinol (a nickel-titanium alloy), and are biased apart from eachother (due to angled portions 53a, 53b of the arms 50a, 50b), therebyurging the jaw cups 46a, 46b apart (as seen in FIG. 2). In addition, asthe arms 50a, 50b and the jaws 46a, 46b are preferably integral witheach other, the jaws are preferably formed from a super-elastic or shapemetal. However, it should be appreciated that while it is preferable toform the entire arm and jaw from a super-elastic or shape memory metal,the jaw cups 46a, 46b and proximal ends 51a-b, 51a-b of the jaws 44 maybe made of any other material and attached to the resilient arms 50a,50b by any conventional and appropriate means.

According to the first embodiment of the invention, the proximal end51a, 51b of each arm 50a, 50b is coupled to the distal end 16a of thecoil 16 by crimping/locking with a hollow threaded screw 102 and awasher 104 as best illustrated in FIGS. 3 and 4. The threaded screw 102is substantially cylindrical, and generally includes a head portion 106,a threaded portion 108, and a cylindrical throughbore 110 along itscentral axis. The throughbore 110 is dimensioned to receive and allowlateral movement of the control wire 18. The distal end 112 of the headportion 106 has a diameter substantially equal to that of the outerdiameter of the coil 16, and is provided with two opposing grooves 114a,114b (see FIG. 4a) on the outer perimeter of the distal end 112 of thehead portion 106. Grooves 114a, 114b are dimensioned to receive theangled portion 52a, 52b at the proximal end 51a, 51b of each of thenarrow arms 50a, 50b. The proximal end 116 of the head portion 106 isshaped as a truncated cone (i.e., frustroconical) and has a largerdiameter 118b at the distal end 112 of the head portion 106 and asmaller diameter 118a at the distal end 120 of the threaded portion 108.The threaded portion 108 has a diameter substantially equal to the innerdiameter of the coil 16 and the proximal end 122 of the threaded portion108 includes threads 124 for lockingly engaging the interior of thedistal end 16a of the coil 16.

The washer 104 is substantially cylindrical, and generally includes athroughbore 126 having proximal 128 and distal 130 sections. The distalsection 128 of the throughbore 126 is shaped as a truncated cone, andthe proximal section 130 extends therefrom. It will be appreciated thatthe throughbore 126 of the washer 104 has substantially the sameconfiguration as the proximal end 116 of the head portion 106 of thescrew 102 and distal end 120 of the threaded portion 108 of the screw102. It will now be understood that the throughbore 126 of the washer104 is dimensioned for engaging the proximal end 116 of the head portion106 of the screw 102 and distal end 125 of the threaded portion 108 ofthe screw 102 when the stepped 52a, 52b proximal ends 51a, 51b of thenarrow arms 50a, 50b are positioned about the grooves 114a-b of thethreaded screw 102 as described above. The proximal end 120 of thethreaded portion 108 of the threaded screw 102 is then threaded into theinterior of the distal end 16a of the coil 16. As can be seen in FIGS. 2and 3, the washer 104 is fastened between the head portion 106 of thethreaded screw 102 and the distal end 16a of the coil 16. The stepped52a, 52b proximal ends 51a, 51b of the narrow arms 50a, 50b are thusfastened between the washer 104 and the threaded screw 102.

As can be seen in FIG. 4c, the preferred end effector arms 50a, 50b havea substantially arced shape in cross section with inner and outer curvedwalls 55a, 55b, 56a, 56b. It will be appreciated that the arced shape ofthe arms extends the length of the narrow arms from the jaws 44a, 44b,back to the angled proximal portions 52a, 52b. With this arrangement,the tube 40 will slide easily over the arms as will be describedhereinafter. In addition, the angled proximal portions 52a, 52b of thejaws 44a, 44b matingly engage the grooves 114a, 114b (see FIG. 4a) onthe outer perimeter of the distal end 112 of the threaded screw 102 headportion 106.

Referring to FIGS. 2, 5 and 6, it will be seen that the cylindricalsleeve 40 is coupled to the distal end of the control wire 18 byproviding the sleeve 40 with a lateral hole 45 which engages a bent end18a of the control wire 18. As illustrated, the bent end 18a of thecontrol wire 18 is welded to the hole 45 in the side of the sleeve 40.However, as will be described in detail hereinbelow, other methods ofcoupling the control wire to the sleeve are possible. The cylindricalsleeve 40 is slidably mounted over the cylindrical washer 104 and headportion 106 of the threaded screw 102, and is axially movable over thearced resilient arms 50a, 50b, thereby bending the arms at the gentlybent locations 53a, 53b, and closing the jaws 46a, 46b as shown in FIG.5. As the resilient arms 50a, 50b are made of superelastic metal, theywill immediately return to their original open position (FIG. 2) oncethe cylinder sleeve 40 is retracted. Furthermore, even after repeatedlysliding the cylinder sleeve 40 back and forth over the arms 50a, 50b,the jaw assembly 44 will maintain its original shape due to the abovedescribed properties of the superelastic metal.

As seen in FIG. 6, the jaw cups 46a, 46b have an eccentric, albeitsymmetrical outline with their widest point indicated by the line 47.Distal of the line 47, the jaw cups are substantially hemispherical andproximal of the line 47, the jaw cups are substantially hemi-elliptical.The jaw cups are arranged so that the rims are substantially alignedwhen closed as shown in FIG. 5. It will also be seen from FIGS. 5 and 6that the side walls 57, 57b, 59a, 59b of the jaw cups 46a, 46b tapertowards the arms 50a, 50b to provide a smooth transition from the jawcups to the arms.

From the foregoing description and with reference to FIGS. 1 through 6,those skilled in the art will appreciate that when the spool 22 and theshaft 20 are axially displaced relative to each other, the cylindricalsleeve 40 and the end effectors 44a, 44b are similarly axially displacedrelative to each other, from the positions shown in FIG. 2 to thepositions shown in FIG. 5 and vice versa. When the spool 22 and shaft 20are in the approximate position shown in FIG. 1, the cylindrical sleeve40 and the end effectors 44a, 44b will be in the approximate positionshown in FIG. 2; i.e., with the jaws open. Thus, when the spool 22 ismoved towards the thumb ring 24, or vice versa, the cylindrical sleeve40 and the end effectors 44a, 44b will be brought into the approximateposition shown in FIG. 4; i.e., with the jaws closed. Moreover, it willalso be appreciated that it is preferable to move the thumb ring 24relative to the spool 22, rather than vice versa since that will movethe cylindrical sleeve 40 relative to the end effectors 44a, 44b ratherthan vice versa. This is desirable so that the end effectors are notmoved away from a tissue sample while the jaws are being closed.

Turning now to FIGS. 7a through 7e, the operation of the multiple samplebioptome of the invention is illustrated schematically in sequence. Asseen in FIG. 7a, a first tissue sample is taken by positioning the jawcups 46a, 46b around a tissue 60 to be sampled. The handle 12 of thebioptome 10 is operated as described above so that the cylindricalsleeve 40 is moved distally over the narrow arms 50a, 50b of the jawassembly 44 to the position approximately shown in FIG. 7b. When thesleeve 40 is moved toward this position, the jaw cups 46a, 46b arebrought close to each other and the sharp rims 48a, 48b of the jaw cups46a, 46b engage the tissue 60 and bite into it. Contemporaneously, andas seen with reference to FIGS. 7f-7h, the knife sharp edge 42 of thesleeve 40 severs any tissue 60 extending from the lateral sides of thejaw cups 46a, 46b. A first sample 60a of the tissue 60 is therebytrapped between the jaw cups 46a, 46b and severed from the tissue 60. Itshould be noted that while taking the bite, the coil 16 is not free tostretch, as it is kept longitudinally stiff by the shrink wrap or sheath15 which preferably extends along the length of the coil 16. If desired,a wire can be used instead of the shrink wrap or sheath. The wire, whichwould typically be flat, would be attached to the proximal and distalends of the coil to keep the coil in tension and prevent it fromstretching as the sleeve is moved forward and a bite taken.

With the end effectors 44a, 44b in the position approximately shown inFIG. 7b, the multiple sample bioptome 10 may be relocated to anothertissue area for sampling. The handle 12 of the bioptome 10 is operatedas described above so that the cylindrical sleeve 40 is moved proximallyover the narrow arms 50a, 50b of the jaw assembly 44 to the positionapproximately shown in FIG. 7c. When the sleeve 40 is moved towards thisposition, the jaw cups 46a, 46b are biased apart by the resilience inthe gently bent portions 53a, 53b of their respective arms 50a, 50b. Thejaw cups can then be positioned around a second tissue 61 for sampling.The procedure described above with reference to FIGS. 7a and 7b isrepeated. In this instance, however, as the jaw cups 46a, 46b arebrought into position, the tissue 61 pushes the first sample 60aproximally away from the jaw cups 46a, 46b and into the space betweenthe narrow arms 50a, 50b as seen in FIG. 7c. Those skilled in the artwill appreciate that the tissue sample 60a is typically gummy and pliantand will stick to and move along one or both of the narrow arms 50a, 50bof the end effectors 44a, 44b. The samples will also stick to eachother. Upon the taking of a sample 61a from the tissue 61, both samples60a and 61a are safely trapped between the narrow arms 50a, 50b of theend effectors 44a, 44b as shown in FIG. 7d. The procedure describedabove with reference to FIGS. 7a through 7d is then repeated assuggested in FIG. 7e until the space between the arms 50a, 50b is filledwith samples 60a, 61a, etc. According to a presently preferredembodiment of the invention, four to six samples may be captured betweenthe arms of the jaw assembly. The presently preferred dimensions of theend effectors are approximately 0.45 inch in length by approximately0.095 in height.

FIGS. 7f-7h show a top view of the sequence of operations depicted inside views in FIGS. 7a and 7b. From the top view of FIG. 7f, it can beseen that the tissue 60 extends beyond the sides of the jaw cups 46a,46b. The knife-sharp distal edge 42 of the cylinder 40 severs the tissue60 which extends beyond the jaw cups so that the sample 60a can beremoved from the tissue 60 as shown in FIGS. 7g and 7h.

As mentioned herein above, there are several ways other than welding inwhich the distal end 18a of the control wire 18 may be coupled to thecylindrical sleeve 40. In particular, FIGS. 8a through 9b show two othermechanisms for coupling the distal end of the control wire 18 with thesleeve.

As shown in FIGS. 8a and 8b, the distal end 18a of the control wire 18is provided with a Z-bend. The side wall of the cylindrical sleeve 40 ispunched with two spaced apart semicircular holes 145a, 145b leaving abendable narrow strip 145c between them. The narrow strip 145c is bentradially inward a distance sufficient to accommodate the distal end 18aof the control wire 18. The Z-bend of the distal end 18a of the controlwire 18 is inserted through the space formed between the narrow strip145c and the semicircular holes 145a, 145b as shown in FIGS. 8a and 8b.

As shown in FIGS. 9a, and 9b, the side wall of the cylindrical sleeve 40is punched with a first hole 245a and a second hole 245c which iscircumscribed by the first hole 245a. The first hole 245a is preferablyrectangular, semicircular, or trapezoidal in shape to form a bendabletab 245b which is bent radially inward as shown best in FIG. 9b. TheZ-bend of the distal end 18a of the control wire 18 is inserted throughthe second hole 245c in the bendable tab 245b as shown in FIGS. 9a and9b.

FIGS. 10 and 10a show another embodiment of a multiple sample bioptome310 of the invention which is particularly suited for cervical biopsyprocedures or other laparoscopic biopsy procedures where the biopsy siteis approachable in a relatively short and direct path rather thanthrough the long tortuous path of the lumen of an endoscope. In thisembodiment, a proximal actuation mechanism 312 is provided with a fixedhandle portion 324 and a movable lever portion 322 which is coupled tothe fixed handle portion 324 by a pivot pin 323. A hollow tube 340 iscoupled at its proximal end to the movable lever portion 322 of theactuation mechanism 312 by a cross pin 341 or other suitable fasteningmeans. The distal end 340a of the tube 340 is provided with a knifesharp edge 342. A relatively rigid rod 318 extends through the tube 340and is coupled at its proximal end to the fixed handle portion 324 bymeans of a cross pin 319 or other suitable fastening means. The distalend 318a of the rod 318 is hollow and internally threaded with threads370 to receive an externally threaded screw 302.

As best shown in FIG. 10a, the distal end of the rod 318 is coupled to ajaw assembly 344 which includes end effectors 344a, 344b, the screw 302,and a washer 304 In particular, the angled proximal ends 352a, 352b ofthe narrow arms 350a, 350b of the end effectors 344a, 344b are fastenedbetween the washer 304 and the threaded screw 302 which is threaded intothe hollow threaded distal end 318a of the rigid rod 318.

As shown in FIG. 10, the fixed handle portion 324 is provided with alower thumb ring 324a and the movable lever portion 322 is provided witha lower finger ring 322a. The upper end 322b of the movable leverportion 322 is provided with a slot 322c for engaging the cross pin 341and the rod 318 is provided with a slot 317 through which the cross pinpasses. Those skilled in the art will appreciate that the actuationmechanism 312 is manipulated using a conventional scissors-grip. Pivotalmovement of the movable lever portion 322 of the actuation mechanism 312as indicated by the arrows 321 results in linear movement of the tube340 as indicated by the arrows 339. It will also be appreciated that theslots 317 and 322c may be dimensioned to limit movement of the tube 340.Because of the geometry of arms 350a, 350b of the end effectors 344a,344b, movement of the tube 340 relative to the rod 318 results in ariding of the tube 340 over the arms 350a, 350b, and an opening andclosing of the jaws as described above. It should be appreciated that,if desired, the actuation mechanism 312 may be used with the flexiblecoil and pull wire described with reference to FIGS. 1 and 2.Conversely, the actuation mechanism 12 described with reference to FIG.1 may be used with the tube and rod arrangement of FIG. 10. It will alsobe appreciated that instead of making the push rod 318 fixed in thenon-moving handle 324, and the tube 340 movable with the lever 322, thepush rod 318 could move, and the tube 340 could be fixed. With such anarrangement, movement of the lever relative to the handle would causethe end effectors 344a, 344b to be drawn into the tube 340, with thejaws closing, and with the jaws and the sharp end 342 of the tube 340severing the tissue.

It will be appreciated that all of the embodiments of the multiplesample bioptome shown in FIGS. 1-10a can be provided with a cauterycapability. For example, as seen in FIG. 10, a cautery contact 398 isprovided which contacts the rigid rod 318 and extends out of the fixedportion 324 of the handle 312. In addition, the tube 340 is preferablyprovided with shrink wrap or other insulation 399. With thisarrangement, when a cautery current is applied to the cautery contact398, the jaw assembly 344 is electrified via its connection to the rod318. Typically, cauterization would be carried out after a sample isobtained and severed from the surgical site with the jaws still locatedat the surgical site. Because the body of the patient acts as the secondelectrode (ground), current flows from the jaws into the patient at thesurgical site, thereby effecting a cauterization of the surgical siterather than cauterizing the sample in the jaws.

Turning now to FIGS. 11, 11a, and 11b, another embodiment of a jawassembly 444 includes a pair of end effectors 444a, 444b and a mountingscrew 402 for coupling the jaws to the distal end 16a of a flexible coil16. Each end effector 444a, 444b includes a jaw cup 446a, 446bpreferably having an array of radially arranged cutting teeth 448a, 448band a resilient, preferably narrow, arm 450a, 450b which extendsproximally from the jaw cup 446a, 446b. The exterior surface of the jawcup 446a, 446b is preferably provided with a closing cam 447a, 447b asdescribed in co-pending co-owned application Ser. No. 08/412,058, filedMar. 28, 1995, which is hereby incorporated by reference herein. Thenarrow arm 450a, 450b is provided with a mounting hole 452a, 452b at itsproximal end 451a, 451b and a gently angled portion 453a, 453b. At leastthe gently angled portion 453a, 453b of the arms 450a, 450b, andpreferably the entire arms 450a, 450b are formed from super-elasticmetal such as Nitinol, and are biased apart from each other (due toangled portions 453a, 453b of the arms 450a, 450b), thereby urging thejaw cups 446a, 446b apart (as seen in FIG. 11b). In addition, as thearms 450a, 450b and the jaws 446a, 446b are preferably integral witheach other, the jaws are preferably formed from a super-elastic metal.

According to the embodiment shown in FIGS. 11, 11a, and 11b, theproximal end 451a, 451b of each arm 450a, 450b is coupled to the distalend 16a of the coil 16 by crimping/locking with the hollow threadedscrew 402 as best illustrated in FIGS. 11a and 11b. The threaded screw402 is substantially cylindrical, and generally includes a head portion406, a threaded portion 408, and a cylindrical throughbore 410 along itscentral axis. The throughbore 410 is dimensioned to receive and allowlateral movement of the control wire 18 as described above withreference to FIGS. 5-7. The head portion 406 has a diametersubstantially equal to that of the outer diameter of the coil 16, and isprovided with two opposed grooves 414a, 414b on the outer perimeter ofthe head portion 406. The grooves 414a, 414b are provided with sidepeaks 415a, 415b and a raised pin 417a, 417b, and are dimensioned toreceive the proximal ends 451a, 451b of each of the narrow arms 450a,450b. The proximal ends 451a, 451b of the arms 450a, 450b are placed inthe respective grooves 414a, 414b so that the pins 417a, 417b engagerespective mounting holes 452a, 452b. The pins 417a, 417b are flattenedlike rivets and the peaks 415a, 415b of the grooves are folded over thearms as shown best in FIGS. 11a and 11b. The threaded portion 408 of thehollow screw 402 has a diameter substantially equal to the innerdiameter of the coil 16 and threadably engages the interior of thedistal end 16a of the coil 16 as shown in FIG. 11b.

FIGS. 12 and 12a-12c, show yet another embodiment of mounting jaws atthe distal end of a flexible coil. A jaw assembly 544 includes a pair ofend effectors 544a, 544b and a mounting screw 502 for coupling the jawsto the distal end 16a of a flexible coil 16. Each end effector 544a,544b includes a jaw cup (not shown) which is substantially the same asany of the previously described embodiments, and a resilient, preferablynarrow, arm 550a, 550b which extends proximally from the jaw cup. Thenarrow arm 550a, 550b is provided with semi-cylindrical portion 552a,552b at its proximal end 551a, 551b which terminates with a pair ofproximally extending tabs 553a, 553b, 555a, 555b.

According to the embodiment shown in FIGS. 12 and 12a-12c, the proximalend 551a, 551b of each arm 550a, 550b is coupled to the distal end 16aof the coil 16 with the hollow threaded screw 502 as best illustrated inFIGS. 12b and 12c. The threaded screw 502 is substantially cylindrical,and generally includes a head portion 506, a threaded portion 508, and acylindrical throughbore 510 along its central axis. The throughbore 510is dimensioned to receive and allow lateral movement of the control wire18 as described above with reference to FIGS. 5-7. The distal end of thehead portion 506 has a diameter substantially equal to that of the outerdiameter of the coil 16, and is provided with two pair of opposedgrooves 514a, 514b, 516a, 516b on the outer perimeter of the headportion 506. The grooves are dimensioned to receive the proximal ends551a, 551b of each of the narrow arms 550a, 550b, as shown best in FIGS.12b and 12c, with the semi-cylindrical portions 552a, 552b lying on thereduced diameter proximal portion of the head 506, the tabs 553a, 553bresiding in the groove 516a, and the tabs 555a, 555b residing in thegroove 516b. The threaded portion 508 of the hollow screw 502 has adiameter substantially equal to the inner diameter of the coil 16 andthreadably engages the interior of the distal end 16a of the coil 16 asdescribed above.

FIGS. 13, 13a, and 13b show a presently preferred embodiment of couplinga jaw assembly to the distal end of a coil. According to thisembodiment, the jaw assembly 560 includes a pair of end effectors 562a,562b, a mounting screw 564, and a retaining sleeve or washer 566. Eachend effector 562a, 562b includes a jaw cup 568a, 568b and a resilient,preferably narrow, arm 570a, 570b which extends proximally from the cup.The proximal end of each arm 570a, 570b is provided with a mounting hole572a, 572b. In all other respects, the end effectors may incorporatevarious features of the end effectors described above. The mountingscrew 564 is similar to the mounting screw 402 described above. It issubstantially cylindrical, having a head portion 564a, a threadedportion 564b, a through bore 564c, and a pair of diametrically opposedarm receiving grooves 564d, 564e, each of which is provided with anupstanding pin 564f, 564g. In this embodiment, a proximal portion 564hof the screw head 464a has a reduced diameter which is substantiallyequal to the inner diameter of the retaining sleeve or washer 566. Theupstanding pins 564f, 564g are located on this proximal portion 564h ofthe screw head 564a. From the foregoing, those skilled in the art willappreciate that the end effectors 562a, 562b are coupled to the screw564 by placing respective arms 570a, 570b in the grooves 546d, 564e sothat the respective mounting holes 572a, 572b are engaged by therespective pins 564f, 564g. After the arms are so arranged relative tothe screw, the sleeve or washer 566 is placed over the proximal portion564h of the screw head 464a and the proximal ends of the arms arecaptured between the sleeve and the screw head. The threaded portion564b, of the screw is then coupled to the distal end of a coil (notshown) as described above and the sleeve or washer 566 is capturedbetween the coil and the screw head as described above.

As mentioned above, the jaw cups are opened and closed by movement of acylindrical sleeve which is coupled to a control wire. FIGS. 14, 14a,and 14b show another embodiment of a cylindrical sleeve 640 coupled tothe distal end 618a of a control wire 618 for opening and closing a jawassembly 644 which is coupled to the distal end 16a of a flexible coil16. The jaw assembly 644 is substantially the same as any of the variousjaw assemblies described above. Notably, the jaw assembly has tworelatively narrow spaced apart arms 650a, 650b. According to theembodiment of FIGS. 14, 14a, and 14b, a cross member 628 is coupled tothe distal end 618a of the control wire 618. The cross member 628 is adisk segment having two opposite substantially parallel sides 628a,628b, two curved sides 268c, 628d having radii of curvature whichcorrespond to the inner radius of the cylindrical sleeve 640, and acentral bore 628e. The distance between the parallel sides 628a and 628bis less than the distance between the interior surfaces of the arms650a, 650b of the jaw assembly; and the distance between the curvedsides 628c and 628d is substantially equal to the interior diameter ofthe cylindrical sleeve 640. The diameter of the bore 628e issubstantially equal to the diameter of the control wire 618. The controlwire 618 is coupled to the cross member 628 by inserting the distal end618a of the control wire through the bore 628e and crimping the controlwire on either side of the cross member as shown best in FIGS. 14 and14a. The cross member 628 is aligned relative to the jaw assembly 644 sothat it extends freely between the arms 650a and 650b as seen best inFIGS. 14a and 14b. The cylindrical sleeve 640 is coupled to the crossmember 628 by crimping the sleeve on either side of the cross member 628at 699 as seen best in FIG. 14a.

There have been described and illustrated herein several embodiments ofan endoscopic multiple sample bioptome. While particular embodiments ofthe invention have been described, it is not intended that the inventionbe limited thereto, as it is intended that the invention be as broad inscope as the art will allow and that the specification be read likewise.Thus, while the jaw assembly has been disclosed as being formed from aparticular super-elastic metal, it will be understood that othersuper-elastic alloys can be used to achieve the same or similar functionas disclosed herein. For example while the jaws have been disclosed asmade out of a nickel-titanium alloy, they may also be made out of, e.g.,iron-platinum, silver-cadmium, nickel-aluminum, manganese-copper,copper-zinc, nickel-thallium, or any other super-elastic alloy. It willfurthermore be appreciated that while the apparatus of the invention wasdescribed as advantageously permitting the obtaining of multiplebiopsies without removal from the surgical site, the apparatus of theinvention, if desired, could still be used for obtaining single biopsiesat a time. In fact, the endoscopic instrument need not be used fortaking biopsies at all, but could be used as a dissector. In a dissectorembodiment, the tube which causes the arms to close would not have asharp end, and the end effectors could be paddle or otherwise shapedrather than having jaw cups. Moreover, while particular configurationsof the actuation mechanism of the invention have been disclosed, it willbe appreciated that other types of actuation mechanisms could beutilized. Also, while specific couplings of the ends of the coil andcontrol wire have been shown, it will be recognized that other types ofcouplings could be used with similar results obtained. Similarly, whilespecific couplings of the ends of the rigid tube and rod have beenshown, it will be understood that other types of couplings could beused. Moreover, while particular configurations have been disclosed inreference to the jaw assembly, it will be appreciated that otherconfigurations could be used as well. For example, while it is preferredto provide jaws with sharp edges, it will be appreciated that in lieu ofedges, the jaws can be provided with sharp teeth which, in conjunctionwith the sharp cylinder, will provide a cutting ability. Furthermore,while in the second embodiment the inner rod is shown to be stationaryand the outer tube is shown to be adjustable, the outer tube may be madestationary and the rod adjustable. It will therefore be appreciated bythose skilled in the art that yet other modifications could be made tothe provided invention without deviating from its spirit and scope as soclaimed.

We claim:
 1. An endoscopic instrument having proximal and distalportions, comprising:a) a hollow tube member having a proximal end and adistal end; b) first and second end effectors each having arms biasedaway from each other, each of said arms being coupled to said distal endof said hollow tube member; c) a cylindrical member slidably disposedover said distal end of said hollow tube member; d) an actuator having aproximal end and a distal end, said actuator extending through saidhollow tube member; and e) coupling means for coupling said distal endof said actuator to said cylindrical member for causing said cylindricalmember to move relative to said first and second end effectors so as tocause said cylindrical member, in a first position, to extend over atleast a portion of said first and second end effectors so as to forcesaid arms of said first and second end effectors toward each other andassume a relatively closed position, and, in a second position, topermit said first and second end effectors to extend away from eachother and assume a relatively open position, wherein, said couplingmeans comprises a disk segment coupled to said distal end of saidactuator, said disk segment being coupled to said cylindrical member bya crimp in said cylindrical member.
 2. An endoscopic instrumentaccording to claim 1, wherein:said disk segment has two substantiallyparallel sides and two curved sides, said two curved sides being coupledto said cylindrical member.
 3. An endoscopic instrument according toclaim 2, wherein:said disk segment passes between said arms of saidfirst and second end effectors.
 4. An endoscopic instrument according toclaim 1, wherein:said disk segment has a central through bore, saiddistal end of said actuator extends through said through bore and iscrimped on opposite sides of said through bore.
 5. An endoscopicinstrument according to claim 1, wherein:said hollow tube membercomprises a coil.
 6. An endoscopic instrument according to claim 1,wherein:said first and second end effectors each include a jaw cup. 7.An endoscopic instrument according to claim 1, wherein:said actuatorcomprises a wire extending through said hollow tube member and coupledto said disk segment, and handle means coupled to said wire and to saidtube member, said handle means for moving said wire relative to saidtube member.
 8. An endoscopic instrument according to claim 1,wherein:said arms are made from a superelastic metal.